GEOLOGY

Detailed explanation-1: -At first the driving force for spreading was argued to be convection currents in the mantle. Since then, it has been shown that the motion of the continents is linked to seafloor spreading by the theory of plate tectonics, which is driven by convection that includes the crust itself as well.

Detailed explanation-2: -Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor. Eventually, the crust cracks.

Detailed explanation-3: -This “recycling” process, later named “seafloor spreading, ” carries off older sediment and fossils, and moves the continents as new ocean crust spreads away from the ridges. Supporting Wegener’s theory of continental drift, Hess explained how the once-joined continents had separated into the seven that exist today.

Detailed explanation-4: -Evidence of Sea Floor Spreading. Harry Hess’s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory. This evidence was from the investigations of the molten material, seafloor drilling, radiometric age dating and fossil ages, and the magnetic stripes.

Detailed explanation-5: -In 1965, a Canadian geophysicist, J. Tuzo Wilson, combined the continental drift and seafloor spreading hypotheses to propose the theory of plate tectonics. Tuzo said that Earth’s crust, or lithosphere, was divided into large, rigid pieces called plates.